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GBS infections are more common that other illnesses for which pregnant women are sreened, such as down´s syndrome,rubella and spina bifida. Yet, gbs remains generally unknown to the public.

Fortunately,there is testing and a preventive treatment available that can help prevent many of these infections.

NEWS

CONJUGATE GROUP B STREP VACCINE IMMUNOGENIC IN WOMEN.
WESTPORT, Nov 21 (Reuters) - An experimental vaccine made up of Group B Streptococcus capsular polysaccharides conjugated with tetanus toxoid evoked a strong antibody response in female volunteers. The result is an important step on the way to a maternal vaccine to prevent neonatal Group B strep (GBS) infection, according to a press release from the NIH, which supported the research. In their paper in the November 15 Journal of Clinical Investigation, Dr. Dennis L. Kasper of Brigham and Women's Hospital, Boston, and colleagues explain that transplacentally acquired anti-GBS antibodies protect against perinatal infection. Efforts to induce maternal immunity have been thwarted by the variable immunogenicity of purified capsular polysaccharides of GBS. To enhance immunogenicity, the researchers developed a polysaccharide-tetanus toxoid conjugate vaccine. Antibody responses in 100 women were measured in a three-way comparison between the conjugate vaccine, a simple polysaccharide capsule vaccine, and a placebo. Dr. Kasper found that at 8 weeks after vaccination, the conjugate vaccine stimulated a greater than fourfold rise in antibody concentration in 90% of recipients, whereas the unconjugated vaccine stimulated this increase in only 50% of the women immunized. Antibodies evoked by the conjugate vaccine were able to neutralize Group B Streptococcus in vitro. In subsequent in vitro experiments, Dr. Kasper injected pregnant mice with either antibodies isolated from women immunized with the conjugate vaccine, or human serum. The offspring were then exposed to an ordinarily lethal Group B Streptococcus challenge. The investigators report that almost three-fourths of the offspring from mice injected with antibodies survived, while all the offspring from mice injected with serum alone died. "These findings demonstrate that the antibodies produced by the conjugate vaccine are able to cross the placental membrane and could confer protection against Group B strep to the fetus," Dr. Kasper comments in the press release. "This is a prototype of what Group B strep vaccines will look like." J Clin Invest 1996;98:2308-2314. -Westport Newsroom 203 221 7648>>>

DOCTORS URGE THE SCREENING OF PREGNANT WOMEN FOR A COMMON GERM. New York Times 1992 Nov 18;142(49,154):B8 Leary WE 930674 Doctors are urging wider screening of pregnant women for group B streptococcus, the cause of 12,000 newborn infections and 2,000 infant deaths in the U.S. a year. Brain damage from meningitis caused by the infection is suffered by 1,600 infants. The bacterium can also cause cerebral palsy, lung and kidney damage, sight and hearing loss, and developmental problems. Group B has been largely ignored because doctors don't know what to do. Group B is different from Group A, which causes sore throats, and is found in 15-40% of healthy women. Only one percent of newborns exposed to the bacterium absorb it into their bodies. The federal government is spending $5 million yearly on group B strep research. Organizations supporting widespread or universal screening include the American Academy of Pediatrics, the American College of Obstetricians and Gynecologists, and the Association of Trial Lawyers of America. The latter called for antibiotics during labor and birth for those at greatest risk of transmitting the bacteria. These include: those who experience premature labor; women under 20 who lacked good prenatal care; those with fever before and during labor; those who experienced early water breaking; those with a previously born strep-infected child; and those with a high bacterial count of group B strep early in pregnancy. A combination rectal and vaginal swab test given 26-28 weeks into pregnancy and costing $20-30 can identify mothers with the bacterium with 90% accuracy.

 THE NEW TEST EVERY PREGNANT WOMAN NEEDS. WOMAN'S DAY 1990 OCT 20;53(15):31,36,37 Squires S 910779 Each year group B streptococcus infects 10,000 American infants and kills 2,000 of them. If the bacteria reaches the brain, it can cause meningitis and the permanent brain damage suffered by half of the survivors. Related to the familiar form causing strep throat, group B strep is harbored by a huge portion of the population, but in adults causes neither symptoms nor harm. University of Alabama's Dr. Barry Gray says 1 in 5 delivering women carries strep B, which can be transmitted to the child in the womb or during birth. Dr. Carol J. Baker, Baylor College of Medicine in Houston, says only half of the children may become carriers, but the 2% who become ill, usually in the first week of life, can lose their lives within hours of becoming symptomatic. First symptoms of sleepiness, fussiness and poor feeding are easily mistaken for colic or a cold. Fever over 100 degrees in a newborn up to 2 months old warrants an immediate call to the doctor, as it is the key symptom. Diagnosis is obtained by a 1-3 day culture, and massive doses of antibiotic are the primary treatment, says Columbia University's College of Physicians and Surgeons' Dr. Joan Regan. Respirators may be needed for the very ill, and all patients need spinal taps to test for meningitis. The Infectious Disease Society for Obstetrics and Gynecology are developing guidelines for screening pregnant women. If a carrier, the pregnancy would be closely screened and, if at high-risk, treated with antibiotics during delivery. Low birthweight and premature babies, babies of carrier mothers with a fever during labor and delivery, babies born 12 or more hours after amniotic fluid breaks, and older children and adults with health problems affecting the immune system are at risk. There are rapid tests available now, which are not totally accurate, but can save babies' lives. Clinical tests on a vaccine should begin soon.

 STREP B INFECTIONS SERIOUS IN NEWBORNS. WASHINGTON POST HEALTH 1992 DEC 22;8(52):15 Siwek J 930469 Group B streptococcus (GBS) is a common germ found in the vagina of 5% to 35% of pregnant women. Most of the time it causes no symptoms, but about one infant in 100 born to a mother with GBS will develop a serious GBS infection. About half of infected infants die and many survivors are left with permanent brain damage. Although GBS does show up on culture tests, treatment early in pregnancy doesn't always keep the infection from returning. The American Academy of Pediatrics (AAP) recently recommended that all pregnant women be cultured for GBS at 26 to 28 weeks of pregnancy. However, even if GBS is detected, the AAP recommends that antibiotic treatment be withheld until delivery and then given only to women at high risk for passing on the infection to their newborn. These include women who go into early labor or have premature or prolonged rupture of the membranes, develop fever during labor, or are pregnant with more than one child. These AAP recommendations are admittedly imperfect, because they don't totally prevent the development of GBS. In addition, since most infants born to infected mothers don't develop the disease, many women and their babies would be unnecessarily exposed to the risk of antibiotic therapy in order to prevent infection in just a few pregnancies. But until a vaccine against GBS is available, the AAP believes that preventive therapy is the best solution to a potentially deadly disease.

 GROUP B STREPTOCOCCAL SEPSIS IN ADULTS AND INFANTS. CONTRASTS AND COMPARISONS. ARCH INTERN MED 1988 MAR;148(3):641-5 Opal SM; Cross A; Palmer M; Almazan R (88133181 NLM) Group B streptococcal infection may result in significant morbidity and mortality in both infants and adults. The experience with group B streptococcal disease was analyzed at one medical center over a ten-year period from 1975 to 1984. Streptococcus agalactiae bacteremia was observed in 29 adults and 26 infants, with an attack rate of 0.2 cases per 1000 adult admissions and 3.2 cases per 1000 live births, respectively. The majority of adult infections apparently occurred as a result of nosocomial acquisition and was associated with a high mortality rate of 38%. Risk factors for group B streptococcal sepsis in adults include diabetes mellitus, malignancy, and hepatic failure. The majority (73%) of neonatal cases occurred within seven days of birth and occurred in a setting of maternal fever, prolonged rupture of membranes, or prematurity. The mortality rate in infants was remarkably low at only 15%. Fatalities occurred in both adults and infants, despite appropriate antimicrobial therapy. Infection control strategies against group B streptococcus must address potential nosocomial dissemination in adults as well as vertical transmission in infants.

 NEW ORLEANS, SEP 18 (REUTERS) - THE 36TH ANNUAL INTERSCIENCE CONFERENCE ON ANTIMICROBIAL AGENTS AND CHEMOTHERAPY is under way in New Orleans, and meeting participants are hearing about the emergence of new infectious diseases and new treatments for diseases that scientists have battled for centuries. Among yesterday's highlights:
VAGINAL COLONIZATION BY GROUP B STREP PREDICTS ADVERSE PREGNANCY OUTCOME... Spanish researchers told the ICAAC audience yesterday that "...Group B Streptococcus colonization [of the vagina] is associated with increased risk of [premature rupture of the membranes] or preterm delivery..." and that the risk is not associated with the density of colonization. In a series of more than 2,000 pregnant women, Dr. Manuel de la Rosa-Fraile of Granada reported finding a Group B Strep colonization rate of 14.6%. The prevalence of premature rupture of the membranes was 35% among women with vaginal Strep colonization compared with 7% among women without vaginal colonization by Group B Streptococcus.

MEDLINE Medline References..GO TO INDEX

1.- de Cueto M; Sanchez MJ; Molto L; Miranda JA; Herruzo AJ; Ruiz-Bravo A; de la Rosa-Fraile M. Efficacy of a universal screening program for the prevention of neonatal group B streptococcal disease. Microbiology Service, Virgen de las Nieves Hospital, Granada, Spain. Eur J Clin Microbiol Infect Dis 1995 Sep;14(9):810-2.

Abstract: Universal antepartum vaginal cultures for group B streptococcus (GBS) were initiated in a Spanish hospital in 1994 using Granada medium. Infants born to carriers were monitored closely, and blood, urine and mucocutaneous areas were cultured for GBS. Group B streptococcus was detected in 543 of 4,525 women (12%). Of these, 454 gave birth vaginally, of whom 201 (44%) received intrapartum ampicillin. Prophylaxis was not administered to 253 women (56%). In this group, infants of 120 women were colonized and 1 case of neonatal GBS disease occurred. Using this protocol, most GBS carriers with risk factors received intrapartum prophylaxis. This protocol also led to early identification of colonized newborns.

2.-Mercer BM; Ramsey RD; Sibai BM. Prenatal screening for group B Streptococcus. I. Impact of antepartum screening on antenatal prophylaxis and intrapartum care.
Department of Obstetrics and Gynecology, University of Tennessee, Memphis, USA. Am J Obstet Gynecol 1995 Sep;173(3 Pt 1):837-41.

Abstract: OBJECTIVE: Our purpose was to evaluate current obstetric practice regarding screening and prophylaxis for group B Streptococcus and to evaluate the impact of screening on antepartum and intrapartum care. STUDY DESIGN: A total of 1232 members of the Society of Perinatal Obstetricians were asked to indicate their practices regarding screening for group B Streptococcus. Respondents were then asked their practices regarding antepartum and intrapartum prophylaxis on the basis of screening cultures, prior antimicrobial treatment, and other risk factors for neonatal sepsis. RESULTS: Of the 925 respondents (75.1%), 30.8% performed routine screening in all pregnancies: first prenatal visit (42.3%), 26 to 28 weeks (41.3%), and 34 to 38 weeks (22.1%). In addition, 65.9% would screen patients only under high-risk situations. Although 70.5% sample multiple sites, respondents were inconsistent regarding the sites from which cultures are obtained: distal vagina (64.2%), cervix (53.9%), proximal vagina (40.0%), anal canal (38.5%), and urethra (4.3%). A total of 34.7% of respondents would treat the patient at the time of a positive culture. Knowledge of maternal group B Streptococcus carriage would significantly alter intrapartum prophylaxis in low-risk (60.3% vs 0.5%) and various high-risk populations (74.0% to 98.4% vs 11.3% to 55.0%). However, no consensus as to optimal practice was identified. CONCLUSIONS: This survey demonstrates significant inconsistencies in screening and prophylaxis for group B Streptococcus by specialists in maternal-fetal medicine. In addition, it reveals that the recommendations of The American College of Obstetricians and Gynecologists and the American Academy of Pediatrics are not routinely followed by these specialists. Knowledge of group B Streptococcus carriage significantly increases antepartum and intrapartum treatment regardless of the presence of other risk factors for neonatal sepsis. The impact of this practice on neonatal therapy warrants further evaluation.
 
 

3.-Mercer BM; Ramsey RD; Sibai BM.
Prenatal screening for group B Streptococcus. II. Impact of antepartum screening and prophylaxis on neonatal care.
Department of Obstetrics and Gynecology, University of Tennessee, Memphis, USA. Am J Obstet Gynecol 1995 Sep;173(3 Pt 1):842-6.

Abstract: OBJECTIVES: Our purpose was to evaluate the current practice of antimicrobial prophylaxis of preterm and low-birth-weight infants and to determine the impact of intrapartum fever, group B Streptococcus carriage, intrapartum antimicrobial therapy, and duration of membrane rupture on neonatal therapy. STUDY DESIGN: A total of 1356 members of the American Academy of Pediatrics were asked their practice regarding neonatal screening and antimicrobial prophylaxis. Respondents were asked to define how maternal fever, group B Streptococcus carriage, intrapartum antimicrobial therapy, and prolonged membrane rupture would affect their decisions regarding neonatal therapy. RESULTS: A total of 982 responses were obtained (72.4%). Routine antimicrobial prophylaxis is given to asymptomatic preterm neonates by 33.7% of pediatricians. Prophylaxis is inconsistently given at 32 to 36 weeks but is nearly universal after intrapartum fever, regardless of intrapartum therapy. If empiric intrapartum prophylaxis was given before a preterm birth, both the incidence (47.1% vs 29.1%) and frequency of prolonged neonatal therapy (30.1% vs 17.4% > or = 7 days) would be increased. Knowledge of maternal group B Streptococcus carriage would lead to a 2.6-fold increase in treatment (75.1% vs 29.1%) and 1.8-fold increase in the incidence of prolonged therapy of preterm infants (30.9% vs 17.4%), with 45.3% giving antibiotics for > or = 1 week if intrapartum treatment had been instituted. Surprisingly, 18% of pediatricians would treat term neonates without any risk factors other than maternal group B streptococcal carriage, and 32.7% would continue treatment for > or = 7 days. The majority of pediatricians (82.6%) felt that intrapartum prophylaxis would reduce early-onset group B streptococcal sepsis, but only 46.0% felt overall neonatal sepsis would be decreased by such therapy. CONCLUSIONS: Antepartum screening and intrapartum prophylaxis against group B Streptococcus by obstetricians may lead to an increased incidence and duration of treatment of preterm and term neonates by the pediatrician. The efficacy, cost, and risk of such treatment in broadly applied screening and treatment programs should be considered before a standard of care is established.

4.-Shermer RH. Group B streptococcus during the perinatal period. Medical College of Virginia Hospitals, USA. J Obstet Gynecol Neonatal Nurs 1995 Jul-Aug;24(6):562-6.

Abstract: The beta hemolytic streptococcus group B (GBS) emerged as a major pathologic threat to infants in the 1960s and continues to be the leading cause of maternal and neonatal morbidity in the 1990s. Current approaches to prevention are directed toward eliminating exposure to the pathogen through chemoprophylaxis or enhancing host resistance through immunoprophylaxis. Because research is advancing rapidly in this area, perinatal nurses should keep abreast of changes in prevention and treatment strategies to enhance patient education and improve care.

5.-Gilbert GL; Isaacs D; Burgess MA; Garland SM; Grimwood K; Hogg GG; McIntyre P.
Prevention of neonatal group B streptococcal sepsis: is routine antenatal screening appropriate. Department of Clinical Microbiology, Westmead Hospital, NSW. Aust N Z J Obstet Gynaecol 1995 May;35(2):120-6.

Abstract: Four strategies for prevention of early onset neonatal group B streptococcal (GBS) sepsis were considered: A: routine antenatal screening for GBS vaginal carriage at 26-28 weeks' gestation and intrapartum antibiotic prophylaxis for all carriers; B: screening as above and prophylaxis only for carriers with risk factors for sepsis; C: prophylaxis for all women with risk factors; D: as for C plus screening at 37 weeks' gestation and prophylaxis for carriers. The outcomes considered for each option were: the proportion of women given prophylaxis; the risk of anaphylaxis; cases of neonatal GBS sepsis and deaths prevented; costs of screening, prophylaxis and of acute care of remaining cases. Published local and overseas studies of neonatal GBS sepsis, effectiveness of antenatal screening and prophylaxis and estimated costs were evaluated. Any of the proposed strategies can prevent a significant proportion of cases of neonatal GBS sepsis and a strategy for prevention of neonatal group B streptococcal sepsis should be part of routine obstetric practice. Strategy C is simple, effective, inexpensive and avoids unnecessary antibiotic use; it is recommended particularly when antenatal care is provided mainly in community or private practice. Strategy A (using vaginal and rectal swabs for screening) could prevent more cases, but at greater cost which could be justified only if protocols can be properly implemented and monitored.

6.-Heimler R; Nelin LD; Billman DO; Sasidharan P.
Identification of sepsis in neonates following maternal antibiotic therapy. Department of Pediatrics, Medical College of Wisconsin, Milwaukee, USA. Clin Pediatr (Phila) 1995 Mar;34(3):133-7.

Abstract: To examine the value of current diagnostic tests identifying neonatal sepsis related to intrapartum treatment with antibiotics, we reviewed the charts of 219 mother-infant pairs, of which 139 mothers received intrapartum antibiotics (group 1) and 80 mothers did not (group 2). When compared with group 2 infants, group 1 infants had fewer positive blood cultures (4.3% vs 20%, P < 0.003), blood cultures positive for group b streptococci (gbs) (p < 0.001), and positive urine gbs latex agglutination (la) tests (p < 0.001). although the sensitivity of the white blood cell count (wbc) was 81%, the specificity was < 60% in both groups. the specificity of the urine gbs la test was 92%. these results suggest (1) the wbc will neither confirm nor rule out neonatal septicemia; (2) blood cultures are indicated in suspected neonatal sepsis even if there was maternal intrapartum treatment with antibiotics; and (3) a urine gbs la test is a useful adjunct in the diagnosis of neonatal gbs septicemia.

7.-Schuchat A.
Group B streptococcal disease in newborns: a global perspective on prevention. Childhood and Respiratory Diseases Branch, National Center for Infectious Diseases, Centers for Disease Control and Prev Biomed Pharmacother 1995;49(1):19-25.

Abstract: Group B Streptococcus (GBS) is an important cause of neonatal sepsis in many areas. Although incidence data are available for a minority of countries, the magnitude of illness due to this bacterium appears to vary substantially. Disease may vary due to the prevalence of asymptomatic GBS colonization, the virulence of circulating strains, the frequency of predisposing conditions such as low birth weight, or differences in obstetric practices. Approaches to prevention of neonatal GBS disease include administering antibiotics to high risk mothers intrapartum, use of intrapartum vaginal disinfectants, development of GBS vaccines, and nonspecific approaches. Determinants of prevention policies in a given area depend on the incidence of disease, the structure of health care delivery, cost-effectiveness, and cultural attitudes. Much GBS disease among newborns is now preventable, yet data on incidence are needed to guide selection of appropriate approaches to disease prevention.

8.-Garland SM; Kelly N.
Early-onset neonatal group B streptococcal sepsis: economics of various prevention strategies.
Royal Women's Hospital, Melbourne, Carlton, VIC. Med J Aust 1995 Apr 17;162(8):413-7.

Abstract: OBJECTIVES: To evaluate three strategies for preventing group B streptococcal neonatal sepsis in large teaching hospitals and to examine their cost effectiveness and cost benefit. METHODS: A decision tree was constructed to determine the outcome of three prevention strategies: (1) Screen all pregnant women for group B streptococcus (GBS) at 28 weeks' gestation and give intrapartum chemoprophylaxis to all GBS carriers; (2) Screen all pregnant women, but give chemoprophylaxis selectively to those carriers with obstetric risk factors (i.e., premature labour, prolonged rupture of membranes and maternal sepsis); and (3) Do not screen but give intrapartum chemoprophylaxis for all women with obstetric risk factors. Australian data were used if available, and the cost benefit and cost effectiveness of each strategy compared with no screening at all were estimated. RESULTS: All three strategies had a net cost benefit compared with no intervention at all. Strategy 1 could prevent 46%, Strategy 2 38% and Strategy 3 60%-80% of all early-onset GBS sepsis. CONCLUSION: A substantial proportion of early-onset GBS sepsis is preventable. Strategy 1, which is practical in some large teaching hospitals, prevents more sepsis at a lower cost per case prevented than Strategy 2. Strategy 3 theoretically could prevent more cases at a substantially lower cost than Strategies 1 or 2, but has not been evaluated clinically.

9.-Obstet Gynecol 1994 Nov;84(5):816-9. Yancey MK; Duff P; Clark P; Kurtzer T; Frentzen BH; Kubilis P.

When confounding variables were controlled in a multivariate analysis, the association between group B streptococcal colonization and chorioamnionitis, but not endometritis, was confirmed. Intrapartum vaginal colonization with group B streptococci is an important independent risk factor for chorioamnionitis.

10.-Obstet Gynecol 1994 Oct;84(4):496-500. Obstet Gynecol 1994 Oct;84(4):496-500. Gibbs RS; McDuffie RS Jr; McNabb F; Fryer GE; Miyoshi T; Merenstein G.

OBJECTIVE: To assess the feasibility and efficacy of a protocol for universal screening for group B streptococci combined with selective intrapartum prophylaxis at a teaching hospital. METHODS: This is a descriptive study of experience with a standardized protocol in which patients were screened at 26-28 weeks with a rectal and genital culture placed directly in selective media. As risk factors, we used clinical chorioamnionitis, preterm birth, and rupture of the membranes greater than 12 hours. Of culture-positive women, 35% developed risk factors (9% chorioamnionitis, 13% preterm birth, and 13% membrane rupture greater than 12 hours at term).

11.-Am J Obstet Gynecol 1994 Feb;170(2):521-6. Katz VL; Moos MK; Cefalo RC; Thorp JM Jr; Bowes WA Jr; Wells SD.

OBJECTIVE: Our purpose was to evaluate and report the results of a protocol for the identification and treatment of all group B streptococcal carriers. STUDY DESIGN: In 1991 we instituted a protocol of antepartum cultures for group B streptococci on all pregnant women who attended clinics at the University of North Carolina Hospitals. Cultures were obtained from the lower third of the vagina and rectum at 24 to 28 weeks' gestation. Women with positive cultures were treated with intravenous antibiotics in labor. Women with signs of chorioamnionitis (through intrapartum assessment) were also treated in labor, regardless of carrier status.During the period of evaluation there were no infants infected with group B streptococci and no adverse reactions or complications among women who were treated with antibiotics. CONCLUSION: We found antepartum screening and intrapartum chemoprophylaxis of all group B streptococcal carriers to be an acceptable and effective protocol for reducing perinatal group B streptococcal infections.

12.- Int J Gynaecol Obstet 1993 Jul;42(1):55-9. ACOG Technical Bulletin Number 170--July 1992.

GBS is the leading cause of perinatal bacterial infections in the United States. Selective intrapartum chemoprophylaxis can prevent GBS early-onset neonatal disease and reduce maternal puerperal morbidity. Intrapartum antibiotic chemoprophylaxis of GBS carriers with one or more risk factors substantially reduces the frequency of GBS disease. Benefit may also be obtained from prophylaxis based solely on a knowledge of risk factors if GBS carrier status is unknown. The importance of GBS infection as a perinatal problem and its considerable economic burden justify implementation of chemoprophylactic programs by obstetricians, particularly those who encounter a high proportion of patients with perinatal risk factors in their practices.

13.-Enferm Infecc Microbiol Clin 1993 Feb;11(2):70-9. Bosch J; Ros R; Amoros M; Olivares R; Alvarez E.

BACKGROUND: To prove both the importance of SGB (group B streptococci) as a cause of perinatal infection and the efficacy of a prophylactic treatment in pregnant women with cervicovaginal colonization by SGB. METHODS: Retrospective study of 197 third trimester pregnant women who were carriers of SGB (155 received intrapartum prophylaxis) and of 44 patients with SGB infections during pregnancy, post-partum and neonatal periods. RESULTS: No neonatal sepsis was detected in the group of SGB carrier mothers who received antibiotic prophylaxis. In carrier pregnant women who did not receive prophylaxis, one case of neonatal sepsis by SGB was detected and a greater prevalence of intrapartum fever, and neonatal infection with negative cultures was observed. SGB was frequently isolated as a cause of early sepsis and neonatal meningitis (13 cases), intraamniotic infection (12 cases) and puerperal endometritis (8 cases). In 45% of the patients with perinatal infections by SGB, the cervicovaginal culture performed in the third trimester of pregnancy did not detect the presence of SGB. CONCLUSIONS: The administration of intrapartum ampicillin to pregnant SGB carriers permits the prevention of perinatal infections by this microorganism in a great number of patients, although the possibility of late colonization, which may not be detected during pregnancy, stil remains.

14.-Pediatr Med Chir 1995 Jul-Aug;17(4):307-9. Diani F; Turinetto A; Tanganelli E.

While our understanding of Group B Streptococcal infections has progressed with impressive measure, their prevention has not been accompanied by an effective means. Chemoprophylaxis for selected colonized women at rupture of membranes or at onset of labour, enhances benefit and minimizes adverse effects. Two or more maternal risk factors are special circumstances for routine use of chemoprophylaxis in asymptomatic neonates. Immunoprophylaxis by IgG antibodies directed against the type-specific polysaccharide antigen of GBS may be provided by passive or active immunization. Hyperimmune i.v. globulins or vaccination of adult women with low levels of antibodies in their sera have been demonstrate to be protective in vivo.

15.-Curr Opin Pediatr 1995 Feb;7(1):13-8. Boyer KM.

Group B streptococci remain a leading cause of life-threatening neonatal infection worldwide. The current estimate of incidence in the United States is 1.8 cases per 1000 live births, with a case-fatality ratio of 10% to 20%. Advances in understanding of the pathogenesis of septic shock and meningitis are yielding new approaches to the treatment of these serious infections. Selective intrapartum chemoprophylaxis with ampicillin has been shown to be both effective and cost effective and is gaining more widespread acceptance as a preventive measure. Conjugate vaccines consisting of type-specific group B streptococci capsular polysaccharides coupled to tetanus toxoid or protein membrane antigens of group B streptococci have been shown to prevent neonatal infection in a mouse model of maternal immunization. Such vaccines are now in trials of safety and immunogenicity in humans.

16.-J Am Acad Nurse Pract 1994 Aug;6(8):357-61. Gallagher RJ; Fuller CA.

Group B streptococcal (GBS) disease, a life-threatening infection in newborns in the United States, causes considerable neonatal morbidity and mortality. GBS is also a major source of maternal infection. Screening during pregnancy leads to early identification. Intrapartal treatment of affected mothers can prevent harmful neonatal effects. Implementation of screening and treatment protocols is recommended for the protection of all obstetric and neonatal patients.

17.-Nippon Sanka Fujinka Gakkai Zasshi 1994 Jun;46(6):497-502. Hoshina K; Kadoi N; Nishida H; Kaneko K; Matsuda S.

Group B streptococcal (GBS) infections in neonates have been a leading cause of bacterial infections. In many cases the infected neonates and young infants died or sequelae remained. The trend of cases, risk factors and prognosis of this disease have been the subjects of questionnaires for the past 5 years in Japan. The number of cases has increased year by year. Risk factors including amniotic turbidity, chorioamnionitis, premature rupture of membrane and fever during labor were recognized in 58% of early onset (less than 7 days of age) and in 28% of late onset (7 days and more of age) infant disease. Cases of death and remaining sequelae were 63(20.8%) of 303 early onset, 27(39.1%) of 69 late onset and 90(24.2%) out of a total of 372 cases. These results suggested that strategies for the prevention of GBS infections in the newborn are necessary.

18.-Am Fam Physician 1994 Feb 1;49(2):434-42. Platt MW; Gilson GJ.

Group B streptococcus is the major cause of neonatal sepsis in the United States. It is estimated that 2,000 infants die annually of syndromes related to group B streptococcus infection. In the early-onset syndrome, transmission is from mother to child, either in utero or during birth. Pneumonia is the most common presentation in infants who develop symptoms during the first seven days of life. The principal manifestation of late-onset infection is meningitis, which occurs in 85 percent of this group. Although group B streptococcus infection is normally remediable with penicillin therapy, rapid diagnosis and treatment are necessary to prevent the serious consequences of the disease. A vaccine is under development, although the cost-effectiveness of a widespread immunization program for a disease with such a low frequency is still unknown. The potentially serious outcomes of this infection, however, make it a major problem for physicians involved in neonatal care.

19.-J R Soc Med 1993 Dec;86(12):712-5. Steele RW.

Group B beta-haemolytic streptococcus (GBS) is the leading cause of life-threatening perinatal infection in developed countries. As immunization of women is not yet available, selective intrapartum chemoprophylaxis appears to be the best current strategy for preventing disease. All pregnant women should be screened for GBS at 26 to 28 weeks gestation. During labour, all colonized women with risk factors for invasive GBS neonatal infection should be treated with intravenous penicillin or ampicillin. Risk factors include preterm labour, premature rupture of membranes, intrapartum fever, multiple births, prolonged rupture of membranes, maternal diabetes, previous sibling with invasive GBS disease, and maternal GBS bacteriuria. The latter two categories warrant chemoprophylaxis regardless of maternal colonization status.

20.-Clin Obstet Gynecol 1993 Dec;36(4):832-42. Katz VL.

GBS is a bacterium that may cause devastating disease. The puzzle of GBS management revolves around the fact that the organism colonizes 15-30% of women, yet produces infection in only 1-3% of the women who are colonized. Neonatal infection is acquired from the maternal genital tract. It ascends across the cervix into the amniotic cavity and also may be acquired during delivery. Manifestations of disease in the fetus and neonate may be out of proportion to those in the mother. Treatment strategies involve the screening all pregnant women with cultures at 26-28 weeks' gestation and rapid tests at the time of labor. Rapid testing has not proven successful, although current research should provide effective and sensitive rapid tests by the end of the decade. Once a woman is known to be GBS positive in labor, there are two options. Most investigators recommend giving chemoprophylaxis only to women who are at high risk for GBS infection--women with preterm labor, ruptured membranes for longer than 12-18 hours, or intrapartum fever higher than 37.5 degrees C. Others advocate treating all GBS carriers regardless of risk status. Treatment of mothers in labor eradicates vaginal carriage of GBS, though it does not eradicate GBS from the lower digestive tract. Intrapartum chemoprophylaxis decreases the incidence of neonatal colonization and significantly decreases the risk of infant disease. In the future, GBS infection probably will be prevented with immunoprophylaxis and vaccination.

21.-Akush Ginekol (Mosk) 1994;(6):31-3. Kosheleva NG; Zatsiorskaia SL.

A retrospective analysis of the course of pregnancy, labor and its outcome for the fetus and newborn in 103 women in whose lochia group B Streptococcus was found showed a high incidence of pregnancy complications (threatened abortions in 36.9%, late gestosis in 40.7%; high incidence (21.3%) of acute respiratory viral infections during pregnancy; 27.5% of women suffered from chronic pyelonephritis. Preterm labor occurred in 21.7% of cases. Preterm escape of amniotic fluid and rapid parturition took place in 43.7% of women. Perinatal mortality was 12.6%. Pathomorphologic examination of newborns who died in labor or later revealed intrauterine pneumonia in all the cases. Coincidence of the agent serotypes in the mother and child confirmed the fact of intrauterine infection.
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Articles published by New England Journal of Medicine:

Rapid Detection of Group B Streptococci in Pregnant Women at Delivery